Johnson City, TN has a population of 65,415 and is the 571st largest city in the United States. The population density is 1,517 per sq mi which is 891% higher than the Tennessee average and 1574% higher than the national average. The median age in Johnson City is 36 which is approximately 7% lower than the Tennessee average of 39. In Johnson City, 49% of the population over 15 years of age are married, 94% speak English and 2% speak Spanish. 56% of Johnson City residents were born in Tennessee, 38% were born out of state, 1% were born outside of the United States and 5% were foreign born.